Nuclear Submarines: America's New Aircraft Carriers?

A new class of nuclear-powered guided missile submarines could be the key to maintaining America’s future naval supremacy as new weapons increasingly challenge the dominance of the U.S. Navy’s aircraft carriers.

In fact, some analysts have suggested that guided missiles submarines should one day replace the aircraft carrier as the centerpiece of the Navy’s warfighting capability.

With the proliferation of precision-guided weapons like anti-ship cruise missiles, anti-ship ballistic missiles and advanced air defense systems—particularly by China—the U.S. Navy’s carriers and their embarked air wing are increasingly vulnerable to what the Pentagon calls the anti-access/area denial (A2/AD) challenge.

Instead of being able to push in close to shore during the initial stages of a major war, the Navy’s multi-billion dollar floating airfields and their escorting warships might be forced to maintain station as far as a thousand nautical miles offshore to remain outside the range of enemy attack. Further compounding the problem is the fact that the current carrier air wing does not have the necessary reach or ability to penetrate into ever more capable enemy air defenses. Even the belated introduction of the Lockheed Martin F-35C Joint Strike Fighter around 2019 will not solve that problem.

While a new long-range stealthy unmanned strike aircraft could eventually give the carrier the long-range reach and hitting power it needs, there are those who argue that submarines are far more effective weapons against such high-end threats. Though potential enemies like China can challenge the United States in the air, sea, surface, on land and in space—American forces dominate the undersea realm with near impunity.

Hendrix argues that the vessels like the first four Ohio-class nuclear-powered submarines that were converted from carrying a payload of 24 Trident II D5 ballistic missiles to a conventional payload of 154 Tomahawk cruise missiles are some of the most potent weapons against an A2/AD threat. “Those submarines have been noticed by nations that would build A2/AD environments,” Hendrix said.

Hendrix makes the case that the vessel’s performance during Operation Odyssey Dawn against the regime of now-deposed Libyan strongman Muammar Gaddafi in 2011 is an indication of just how potent such submarines can be. USS Florida (SSGN-728) almost single-handedly eliminated Libya’s air defenses with a barrage of some 90 Tomahawk cruise missiles.

These SSGNs are so capable that Hendrix suggests that the Navy cease building the new Ford-class nuclear-powered aircraft carriers after the two vessels currently under construction are completed. The Navy could buy numerous SSGNs for the price of a single new aircraft carrier—a new Ford-class carrier costs roughly nearly $13 billion without factoring in the price of the air wing.

Unlike a carrier, an SSGN would be able to approach an enemy coast before disgorging its payload of missiles—striking deep inland with weapons that have a range of more than 1,200 nautical miles to hit targets that might include everything from air defenses, to command and control nodes, to enemy infrastructure. “The point there is that three SSGNs gives you a potential striking power of 462 Tomahawk missiles or Tomahawk follow-ons that would be even more advanced,” Hendrix said.

Hendrix said that there is an immediate opportunity to expand the SSGN fleet by converting the last two Ohio-class ballistic missile submarines into cruise missile carriers. Those two vessels are coming up on their mid-life refuelling and overhauls, which gives the Navy the perfect opportunity to convert those submarines to a conventional strike role.

In the future, the Navy should consider buying the Ohio Replacement Program (ORP) ballistic missile submarines two at a time to help reduce the astronomical cost of those vessels, Hendrix said. One submarine in each block could be completed as a ballistic missile submarine while the other could be built as a cruise missile carrying variant. Ultimately, Hendrix would build eight SSGNs and twelve boomers for a total production run of twenty ORP submarines. “I would build them together in order to get efficiencies of scale and perhaps get a cost break,” Hendrix said. “In the eight SSGNs, we’d have well over 1,100 precision strike weapons.”

But the SSGNs would not just be useful for their missile payload, Hendrix pointed out. The vessels could alser, if needed, the mao carry various unmanned aircraft and unmanned underwater vehicles (UUVs) onboard. Furthssive boats could carry pre-packaged satellites that could be launched into low Earth orbit to replenish U.S. space capabilities in case existing space assets are attacked or destroyed during a full-on great power conflict, Hendrix said.

The U.S. Navy is planning on building new Virginia-class attack submarines with additional cruise missile carrying capabilities in the form of four additional payload tubes. Hendrix said he supports building those vessels only because it is too late to halt the program. The modified Block V Virginia-class attack submarine would be a useful supplement to an SSGN version of the ORP submarines, but with smaller missile tubes, those boats would not be able to fit new weapons with the kind of range and payload the larger vessels could.

Bryan Clark, a former U.S. Navy nuclear submarine officer and analyst at the Center for Strategic and Budgetary Assessments, agreed with Hendrix that submarines might be the best option during high-end combat operations. “Against the Chinese A2/AD complex, I agree undersea systems and a long-range survivable UCLASS/UCAV are the most viable approaches for strike and ASuW [anti-surface warfare] in wartime,” he said.

But submarines do have limitations, Clark pointed out. “In general submarines are constrained by their limited situational awareness, slow speed, and lack of self defense. This makes them likely to evade when counter detected and/or attacked,” Clark said. “Our SSNs [attack submarines] are very susceptible to this, because they are expensive, important capital assets. Our commanders will choose to evade and come back later rather than stand and fight.’’

Moreover, while China’s anti-submarine warfare (ASW) capabilities are not particularly impressive, the People’s Liberation Army Navy (PLAN) might still be able to mount a formidable defense close to their own shores, “While the PLA(N)'s ASW capabilities are pretty modest, I wouldn't discount the ability of the PLA to mount an effective ASW campaign in their littoral waters,” Clark said. “One advantage ASW forces have is they just need to prevent submarines from getting into position and carrying out their operations to be effective. They don't need to kill the submarines. The PLA can pull this off by using seabed sensors, active sonars, and missiles with torpedo and depth bomb warheads.”

That means that even a submarine might have trouble operating close Chinese waters without help. “If the PLA(N) can harass and hinder our submarines within 200-300 nautical miles from their coast, we will not be able to effectively conduct ASUW and strike against some of our high-priority targets,” Clark said. “This means we need other means to operate under Chinese coastal waters. This is where UUVs—large, long-endurance and small, sub-launched—and undersea power and sensor systems will be needed.”

But while submarines are extremely effective weapons during a high-end fight, their very stealth and endurance might actually cause an enemy to escalate a conflict. “While submerging more combat power might make the total force more effective in wartime, it may have the unintended consequence of making that war more likely to happen because Chinese adventurism and its propensity to compel behavior would necessarily be less strongly challenged,” said former naval officer Bryan McGrath, managing director of the FerryBridge Group naval consultancy. “Moving precipitously in this direction is unwise.”

McGrath said that submarines simply do not project power well because friendly nations do not see a visible American presence—and neither does the enemy. “A big part of our strategy is to demonstrate commitment, to assure friends and allies by our presence and to deter through visible combat power,” McGrath said. “Submarines simply cannot do this very well.”

To dissuade Chinese assertiveness or deterring Chinese aggression, the U.S. needs “a visible day-to-day presence backed up by these demonstrated combat capabilities,” Clark said. That could include lower-end vessels like the Littoral Combat Ship or amphibious assault ships. “You may want to consider the use of lower-end ‘presence’ forces in peacetime…to show China and our allies and partners we are there and have skin in the game,” Clark said. “If conflict starts, our forces will be in the middle of it. You can call that a tripwire, but regardless of what it is called, these forces represent U.S. resolve and will compel a U.S. response if they are attacked, even collaterally.”

Hendrix acknowledges the concern of U.S. allies who say that submarines just do not provide the same reassurance as a visible American presence. “I’ve been told that to my face by foreign governments, that submarines don’t carry that visible sense that the Americans are there,” he said. As such, Hendrix said he agrees that the U.S. Navy needs a better high-low mix of capabilities. That would mean that the service should consider buying more frigates and lower-end destroyers. “You need a visible presence,” Hendrix said.

Hendrix said that while some might argue that perhaps a smaller U.S. vessel might not be a particularly threatening/effective deterrent, if a potential adversary were to harass such a ship there are ways for submarines to make it known that they are in the area lurking unseen. Moreover, a vessel like an SSGN—where an astute enemy might have an inkling that something is hiding beneath the waves—can cause a potential enemy to be worried when they are not sure exactly where it is and thereby act as a deterrent. “What makes people worry about them is what they don’t know,” Hendrix said.

Dave Majumdar has been covering defense since 2004. He currently writes for the U.S. Naval Institute, Aviation Week and The Daily Beast, among others. Majumdar previously covered national security issues at Flight International, Defense News and C4ISR Journal. Majumdar studied Strategic Studies at the University of Calgary and is a student of naval history.